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Plasma experiments with 1. 06. mu. m lasers at Lawrence Livermore Laboratory

Description: Recent laser fusion experiments at Lawrence Livermore Laboratory have provided basic data concerning laser beam propagation and absorption in high temperature plasmas, electron energy transport processes that transfer the absorbed laser energy to the high density ablation region, the general fluid dynamic expansion and compression of the heated plasma, and the processes responsible for the production of 14 MeV neutrons during implosion experiments. This paper reports results related to the prop… more
Date: March 12, 1976
Creator: Alhlstrom, H. G.; Holzrichter, J. F.; Haas, R. A.; Storm, E. K.; Manes, K. R.; Phillion, D. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Scheme for evaluating T/sub E/T/sub I/ and anti Z by light scattering

Description: When highly ionized impurities are present in a plasma, the scattered spectrum of the major ion species can be distorted in a complicated way. A method is given by which T/sub e/T/sub i/ and anti Z (identical with sigma n/sub j/z/sub j//sup 2//n/sub e/) can be measured which does not require any knowledge of the mass, charge state, or concentration of the impurity species. A generalization of the Salpeter approximation for the integrated cross-section is proven. The result is that the total cro… more
Date: March 1, 1976
Creator: Bretz, N. L.
Partner: UNT Libraries Government Documents Department
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Phase controlled rectifier study

Description: This report introduces the results of an engineering study incorporating a computer program to determine the transient and steady-state voltage and current wave shapes for a 12-pulse rectifier system. Generally, rectifier engineering studies are completed by making simplified assumptions and neglecting many circuit parameters. The studies incorporate the 3-phase AC parameters including nonlinear source or generator, 3-winding transformer impedances, and shunt and series capacitors. It includes … more
Date: March 1, 1976
Creator: Bronner, G. & Murray, J. G.
Partner: UNT Libraries Government Documents Department
open access

The Uranium-Tritium System - The Storage of Tritium

Description: The thermodynamics of the uranium-tritium system were determined over the pressure range of 2 x 10 to the minus 4 to 20 atm from experimental composition-pressure-temperature data. Both enthalpy and entropy were shown to vary slightly with composition by analysis of van't Hoff plots for the U-D system and the U-T system. The evolution of helium-3 borne in the lattice of a fully tritiated sample of uranium was studied over a period of several months, and the relative proportion of helium-3 and t… more
Date: March 1, 1976
Creator: Carlson, R. S.
Partner: UNT Libraries Government Documents Department
open access

Stacking sequence periodicites in silicon carbide

Description: Direct lattice imaging by transmission electron microscopy and optical diffraction were combined to study the stacking sequences in fine-grained (<1 ..mu..m), hot-pressed SiC. Stacking periodicities of 5, 6, 7, 8, 24, 36, and 48 composite Si-C layers were recognized. (DLC)
Date: March 1, 1976
Creator: Clarke, D. R. & Thomas, G.
Partner: UNT Libraries Government Documents Department
open access

Review: BNL graphite blanket design concepts

Description: A review of the Brookhaven National Laboratory (BNL) minimum activity graphite blanket designs is made. Three designs are identified and discussed in the context of an experimental power reactor (EPR) and commercial power reactor. Basically, the three designs employ a thick graphite screen (typically 30 cm or greater, depending on type as well as application-experimental power reactor or commercial reactor). Bremsstrahlung energy is deposited on the graphite surface and re-radiated away as ther… more
Date: March 1, 1976
Creator: Fillo, J. A. & Powell, J. R.
Partner: UNT Libraries Government Documents Department
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Using local momentum to disentangle angular distributions. [Optical model, DWBA]

Description: Optical model elastic and DWBA transfer angular distributions are studied by isolating their positive and negative deflection angle components. The local angular momentum of these amplitudes allows isolation of the regions of angular momentum space that are contributing to the different angular regions of the cross sections. This information can be employed to isolate features of the cross sections arising from orbiting, reflection, Coulomb rainbows, nuclear rainbows, Regge poles, etc. Specific… more
Date: March 1, 1976
Creator: Fuller, R. C. & Moffa, P. J.
Partner: UNT Libraries Government Documents Department
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Implications for new particle searches of some cosmic ray emulsion events. [Cross sections]

Description: Calculations of backgrounds for cosmic ray candidates for new particles in emulsions are summarized. Even if only the strongest cosmic ray candidates are accepted as genuine, the implication is that their production cross sections would be relatively large at accelerator energies (greater than or equal to 1..mu..b) and that decay modes with ..pi../sup 0/ appear to be prominent. Current accelerator upper bounds on sigma x B/sub K pi/ for production of hadrons with M greater than 2 GeV and the re… more
Date: March 1, 1976
Creator: Gaisser, T. K.
Partner: UNT Libraries Government Documents Department
open access

Status of large neodymium glass lasers

Description: The elements of a Nd: Glass laser chain as it is constructed for fusion experiments are described. A brief overview of the ARGUS and SHIVA systems employing Nd lasers is given. (MOW)
Date: March 15, 1976
Creator: Glaze, J. A.; Simmons, W. W. & Hagen, W. F.
Partner: UNT Libraries Government Documents Department
open access

Physical basis for large forward cross sections in /sup 60/Ni(/sup 18/O,/sup 16/O) reaction

Description: Experiments on the reaction /sup 60/Ni(/sup 18/O,/sup 16/O)/sup 62/Ni revealed an unexpectedly large forward cross section for production of the ground state, in contrast with an expected grazing peaked distribution. This has most recently been interpreted in terms of a surface transparent optical potential. In the inverse experiment, it is known that /sup 18/O is produced in its 2/sup +/ state with larger cross section than the ground state. This suggests that the above ground state reaction c… more
Date: March 1, 1976
Creator: Glendenning, N. K. & Wolschin, G.
Partner: UNT Libraries Government Documents Department
open access

New recoil effect in nucleon transfer reactions between heavy ions

Description: In the last few years it has become clear that the effect of the shifting centers of mass (recoil effect) have to be properly incorporated into the theory of single nucleon transfer between nuclei, especially at higher energies. A re-examination of the present theory reveals, however, that there remains a serious problem, which is associated with the so-called spurious center of mass motion in nuclear structure models. In principle the present calculations that purport to treat recoil exactly, … more
Date: March 1, 1976
Creator: Glendenning, N. K.; Charlton, L. A.; Delic, G. & Nagarajan, M. A.
Partner: UNT Libraries Government Documents Department
open access

Development scenario for laser fusion

Description: This scenario proposes establishment of test and engineering facilities to (1) investigate the technological problems associated with laser fusion, (2) demonstrate fissile fuel production, and (3) demonstrate competitive electrical power production. Such facilities would be major milestones along the road to a laser-fusion power economy. The relevant engineering and economic aspects of each of these research and development facilities are discussed. Pellet design and gain predictions correspond… more
Date: March 30, 1976
Creator: Maniscalco, J. A.; Hovingh, J. & Buntzen, R. R.
Partner: UNT Libraries Government Documents Department
open access

Diffusive phenomena reflected in the charge and angular distributions of N, Ne, Ar, Kr induced reactions. [Master equation, probability distribution, diffusion, charge and angular distributions, deep inelastic scattering]

Description: The presence of diffusion processes in heavy ion reactions is argued on a theoretical ground by pointing out the limitation of a Lagrangian approach to the time-dependent processes. The master equation is used to describe the diffusion of the probability distribution along the mass asymmetry coordinate. Calculations of the probability distributions as a function of time have been performed for many heavy ion reactions. Experimental evidence of diffusion is shown to exist in the charge and angul… more
Date: March 1, 1976
Creator: Moretto, L. G. & Sventek, J. S.
Partner: UNT Libraries Government Documents Department
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Proceedings of the first ERDA statistical symposium, Los Alamos, NM, November 3--5, 1975. [Sixteen papers]

Description: The First ERDA Statistical Symposium was organized to provide a means for communication among ERDA statisticians, and the sixteen papers presented at the meeting are given. Topics include techniques of numerical analysis used for accelerators, nuclear reactors, skewness and kurtosis statistics, radiochemical spectral analysis, quality control, and other statistics problems. Nine of the papers were previously announced in Nuclear Science Abstracts (NSA), while the remaining seven were abstracted… more
Date: March 1, 1976
Creator: Nicholson, W L & Harris, J L
Partner: UNT Libraries Government Documents Department
open access

Microstructure of Fe--Cr--Co--Nb--Al permanent magnet

Description: The microstructure of an Fe-Cr-Co-Nb-Al permanent magnet is described. An effect of a thermomagnetic treatment on the microstructures is also discussed since a thermomagnetic treatment plays an important role in producing good magnetic properties in this alloy. Investigation results show that the magnetic properties of the alloy do not depend on the crystal orientation. This is confirmed by the measurement of the magnetic properties of Fe-30 wt percent Cr-23 wt percent Co single crystals.
Date: March 1, 1976
Creator: Okada, M.; Homma, M.; Kaneko, H. & Thomas, G.
Partner: UNT Libraries Government Documents Department
open access

D. C. electric field behavior of high lying states in atomic uranium

Description: The effects of D. C. electric fields on high lying Rydberg and valence states in atomic uranium have been studied. Results of measurements of Stark shifts, lifetime lengthening via l-mixing, critical fields for ionization, barrier tunneling, and the appearance of zero-field parity forbidden transitions are presented for atomic uranium along with the observation of field induced autoionization of valence states. 3 figs. (GHT)
Date: March 31, 1976
Creator: Paisner, J. A.; Carlson, L. R.; Worden, E. F.; Johnson, S. A.; May, C. A. & Solarz, R. W.
Partner: UNT Libraries Government Documents Department
open access

F1 phenomenological test on fuel motion. Interim report. [LMFBR]

Description: A description is given of TREAT F-series tests which are being conducted to provide data on fuel motion in an LMFBR during a hypothetical loss-of-flow accident. Fuel and fuel boundary conditions in an LMFBR subassembly following sodium voiding and dryout under loss-of-flow conditions are simulated in each F-series test. Simulation is achieved with a single fuel element surrounded by an annular nuclear heated wall in a dry (no sodium) test capsule. Results are presented and discussed.
Date: March 1, 1976
Creator: Palm, R. G.; Gehl, S. M.; Stewart, R. R.; De Volpi, A. & Rothman, A. B.
Partner: UNT Libraries Government Documents Department
open access

Environmental monitoring problem: optimal solutions for control and surveillance applications in the case of infrequent sampling

Description: An environmental monitor is defined as a system that estimates environmental pollutant levels throughout an environmental region for all times in a specified time interval, using measurement data taken only at discrete locations and at discrete times. Two distinct monitoring problems are posed, the first for environmental feedback control applications, the second for surveillance or pollutant limit violation detection. The main results are for the special case of infrequent sampling. If the req… more
Date: March 1, 1976
Creator: Pimentel, Kenneth D.
Partner: UNT Libraries Government Documents Department
open access

Polarization of single-particle states involved in heavy ion transfer reactions

Description: If two nuclei could be placed next to each other at a distance typical of grazing collisions, the single-particle states in each would adjust themselves to the presence of the other nucleus. They would develop an appreciable probability of being in the other nucleus, and the more weakly bound the state, the more strongly it would be polarized by the other nucleus. The solution to this situation has been realized in the two-center shell model. Whether such an adjustment can occur during a reacti… more
Date: March 1, 1976
Creator: Pruess, K.; Delic, G.; Charlton, L. A. & Glendenning, N. K.
Partner: UNT Libraries Government Documents Department
open access

Two plasmon parametric decay in a slightly inhomogeneous plasma

Description: The convective parametric decay of an incident electromagnetic wave (..omega../sub 0/,k/sub 0/) into two plasmons at ..omega.. = ..omega../sub p/ in a slightly inhomogeneous plasma of scale length L is considered. Asymptotic solutions for the fields are obtained which show that for L/lambda/sub 0/ much greater than (..omega../sub p/lambda/sub D//..nu..lambda/sub 0/)/sup 2/, where ..nu.. is the plasmon damping rate, the homogeneous-plasma decay criterion must be satisfied by the pump field for i… more
Date: March 1, 1976
Creator: Schuss, J. J. & Chu, T. K.
Partner: UNT Libraries Government Documents Department
open access

New apparatus for thermophysical measurements above 2500 K. [Enthalpy, volume, electric resistivity of solid and liquid; pressure dependence of melting point]

Description: An apparatus was developed to make simultaneous measurements of enthalpy, temperature, volume, and electrical resistivity on metals in the temperature range from 2500 to 8000/sup 0/K and at pressures up to 1 GPa. Cylindrical samples are resistively heated by a 10-50 ..mu..s current pulse in a constant pressure inert gas environment. Data for the refractory transition metals Nb, Mo, Ta, and W are presented.
Date: March 1, 1976
Creator: Shaner, J. W.; Gathers, G. R. & Minichino, C.
Partner: UNT Libraries Government Documents Department
open access

Electron-correlation satellites in electron spectroscopy. [Review]

Description: A review is given of electron-correlation satellites in ion and atom emission spectra. The topics developed are the early history using Mn/sup 2 +/ as an example, shake-up satellites and initial-state-configuration interaction (ISCI), direct observation of ISCI by photoemission: the ns/sup 2/ case, and autoionization in Ba and other np/sup 6/ (n + 1)s/sup 2/ cases. (JFP)
Date: March 1, 1976
Creator: Shirley, D. A.; Martin, R. L.; Mills, B. E.; Suzer, S.; Lee, S. T.; Matthias, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Preliminary observations of electron irradiation damage in short-range ordered Ni/sub 4/Mo. [Short-range order]

Description: Experiments were conducted to evaluate the behavior of short-range-order Ni/sub 4/Mo (produced by quenching from above the critical ordering temperature) in an irradiation environment. A 1-MeV electron microscope was used, with the temperature of the irradiated area being approximately 100/sup 0/C. Results indicated that the short-range order is not destroyed by electron irradiation up to 5 dpa, although domain coarsening may occur. (DLC)
Date: March 1, 1976
Creator: Sinclair, R.; Gelles, D. S. & Thomas, G.
Partner: UNT Libraries Government Documents Department
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